I'm not happy about the behaviour of join here, because there is no way how CORE::join() will ever assign to the lvalue.

So it should act like handling copies.

I'm aware that we can override built-ins like join, so accessing the alias should still be possible. Theoretically that is.

Update

On second thought, a general new Warning in case of side effects of altered repeated variables as arguments may be more effective.

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re^4: ${^POSTMATCH} problem by LanX
in thread ${^POSTMATCH} problem by pl_pm

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